A network configuration issue has been detected on the test path. The MTU is too large to reliably detect data errors within packets. In rare cases, data corruption could occur.

Recommended action

Limit MTU size to 12,144 bytes or less.

Detailed explanation

In the case of oversize MTU, very large MTUs, i.e. those greater than 12,144 bytes, should not be used in IPv4 networks. This is because: The CRC-32 checksum loses effectiveness on larger blocks; the buffer hosts aren't usually tuned for large packets; frame overhead is infinitesimal at sizes greater then 9000; and the probability of loss increases approximately linearly with packet size.

Possible secondary messages

  • "CRC-32 checksum used by TCP/IP, and other transport protocols, is not reliable for packets larger than 12,144 bytes"

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